Wednesday
May062015

Bringing the Nutrients Back Into Our Food Nutrient Density

In the beginning there were healthy, whole foods packed full of nutrients. Today half the world is plagued by starvation and the other half from too much nutrient-depleted, calorie dense food. Times have changed and so must the way we look at food, nutrition and our health.

The modern day processed “white foods” such as sugar, bread, white rice, seed-“vegetable” oils and processed breakfast foods are full of empty calories and low in nutritional value. Unfortunately these foods now make up a large portion of the average Western diet. Meanwhile, most people rarely consume there required intake of fruit, vegetables, nuts, beans and other nutritious food. When they do consume vegetables, often it is in the form of over-processed potatoes without the nutrient-dense peel, and deep fried in “cholesterol and saturated fat free over processed vegetable oils”. The average American, British or Australian eats only one or two vegetables serves per day, a couple of pieces of fruit and a lot of over-processed and nutrient-depleted foods. These nutrient-depleted foods often require nutrients in order to be digested, absorbed, utilised and eliminated from the body. The cost of this may actually deplete the body of nutrients rather than providing them.

It is generally recognised that our bodies require some 90 essential nutrients which include:

16 vitamins;

12 amino acids;

3 essential fatty acids; and

20 or so minerals or trace elements.

As well as a growing list of phytonutrients such as antioxidants.

Rising rates of obesity and type 2 diabetes, cardio-vascular disease cancer and other chronic illnesses continue to be linked to a growing consumption of refined grains, added sugars and “empty calories”, as well as a major nutritional deficiencies. Refined grains, processed vegetable fats, and sweets are inexpensive, palatable, and convenient. However, they can also be energy-dense and are low in vitamins, minerals, and other micronutrients. The World Health Organization has found sufficient evidence to link high consumption of energy-dense foods to the global obesity epidemic and chronic illness.

Concerns that the standard Australian/American diet (SAD) has become energy-rich but nutrient-poor have been expressed for many decades now. Unfortunately, the food industry has consistently slowed positive change and confused the situation even more. Claims like “low fat”, no “added sugar” or “protein enriched” are just perplexing the situation more and causing long term harm. We now know that saturated fat, salt and cholesterol in food is not so bad for us and definitely not the demon it is made out to be by dietetic organizations who derive large sums of money from the sugar and vegetable oil industry. For example, eating foods with cholesterol is not bad for you according to the 2015 Dietary Guidelines Advisory Committee (DGAC) of the US Government. So it is not bad to eat eggs, particularly given that they are relatively nutrient dense and they are much better for you than cereal breakfast foods. Protein enriched breakfast foods also translates to added gluten, the protein linked with gut conditions including celiacs disease. Just recently the sugar industry has been discovered subverting policies to restrict sugar consumption by blocking information linking sugar with tooth decay over many decades. The sugar industry is now attacking the World Health Organisation who want to lower the recommended sugar consumption by even more.

Calorie counting is another example of a distraction from nutrition. Most of the diet programs count calories and barely even touch on nutrition. This is the root cause of why these program don’t work. People make judgments on the foods they eat based on calories, “low fat” or “no cholesterol” rather than eating healthy nutritious foods. Having tunnel vision and simply focusing on these issues at the cost of giving consideration to any of the other food issues is absolutely wrong and will never have a positive effect on your health and wellbeing. Simply counting the calories and balancing it with your exercise is a sure way of developing nutritional deficiency and illness that goes with it. The trick is to choose foods with high nutrient density that fill both needs at the same time. Whole foods tend to have the most nutrients for their calories.

Attempts to translate dietary guidelines into practice, as formulated by professional associations and expert panels have also tended to focus on the negative. In many cases, healthy foods are defined by the absence of problematic ingredients like fat, cholesterol, sugar, and sodium, rather than by the presence of any beneficial nutrients they might contain. In the UK the National Heart Lung and Blood Institute defined healthy foods by low amounts of fat, saturated fat, cholesterol, and sodium per serving. The definition of healthy foods adopted by the American Heart Association was also based on the virtual absence of fat, saturated fat, and cholesterol and on a low sodium content per serving. The demonization of these ingredients has occurred at the expense of more sugar and processed omega 6 fats being added. Both which are inflammatory and linked with many forms of chronic illness. Processed fats and sugary foods don't have the nutrients, vitamins, and minerals that your body needs to be healthy. That's why we call these calories empty. “The World Health Organization has cautioned against the excessive consumption of energy-dense foods, notably those high in sugar and fat.

The National Cancer Institute included in its former definition of healthy foods all fruits and vegetables in their natural form, with the exception of avocados, nuts, olives, and coconut. The exclusion of avocados, now rescinded, and was based purely on fat content and did not take the beneficial nutrients in avocados into account. But going against any common sense and science they still restrict nuts and coconuts. The research on avocados, nuts and coconuts is overwhelmingly positive. It seems these professional guidelines are just opinions.

The key to optimizing your health and achieving your ideal body weight is to eat predominantly those foods that have a relatively high proportion of nutrients (non-calorie food factors) to calories (carbohydrates, fats, and proteins). Adequate consumption of micronutrients—vitamins, minerals, and many other phytochemicals—without excessive calorie intake, is the key to achieving excellent health and weight loss. The nutrient density in your body’s tissue is proportional to the nutrient density of your diet. Dietary guidelines now recommend that consumers replace some foods in their diets with more nutrient-dense options.

Unlike food labels which list only a few nutrients, nutrient density scores are based on many more important nutritional parameters. Nutrient density refers to how many nutrients you can obtain from food, given the number of calories it contains. Similar to the way energy density focuses on calories per serving, nutrient density is a simple way to highlight the link between nutrient content and calorie count. Foods that are nutritionally dense provide the most nutrients for the fewest number of calories. Any systematic nutrient dense score should include fiber, calcium, iron, magnesium, phosphorus, potassium, zinc, copper, manganese, selenium, vitamin A, beta carotene, alpha carotene, lycopene, lutein and zeaxanthin, vitamin E, vitamin C, thiamin, riboflavin, niacin, pantothenic acid, vitamin B6, folate, vitamin B12, choline, vitamin K, Omega 3 and 9 fatty acids as well as other phytonutrients and antioxidants as a percentage of their Dietary Reference Intake (DRI).

Not surprisingly the most nutrient dense foods tend to be plant foods, in particular leafy green vegetables. Also, because phytochemicals (plant based chemicals) are largely unnamed and unmeasured, these rankings may underestimate the healthful properties of colorful, natural, plant foods. The nutrient density of natural whole foods may be even higher. Nutrient density scores demonstrates the nutritional power of green vegetables, particularly compared to processed foods and animal products. Even though attention should be placed on these nutrient rich foods, it is also important to achieve micronutrient diversity.

While there are many challenges associated with nutrient density, it is by far the best indicator of the nutrient base of foods. In reality the energy density of foods is not always determined by their sugar and fat contents. Often, energy-dense foods are simply those foods that are dry. Water, which provides weight but no calories, influences the energy density of foods more than any macronutrient, including fat. Examples of dry energy-dense foods are potato chips, whole grains and cereals. In contrast, fruit, vegetables, and milk are energy-dilute. Although the overall inverse relation between energy density and nutrient density may hold, not all energy-dense foods are necessarily nutrient-poor or vice versa.

The automatic assignment of all energy-dense foods into the “bad” category seems arbitrary and is not based on any particular metric or scale. Furthermore, what can be included in the nutrient density scores is only what is currently available from various databases. For example at present it is limited in antioxidant data.

For maximum effectiveness, nutrient density models need to be transparent, based on publicly accessible nutrient composition data, and validated against independent measures of a healthy diet and should be based on 100 kcal and serving sizes performed better than those based on 100 g.

Nutrient density also has the advantage of shifting attention from diets back to foods and people don’t need a calculator or an advanced degree in math or nutrition to calculate what constitutes a healthy diet.

Wednesday
May062015

Reversing Type 2 Diabetes

In a world of excess, cheap fat and sugar laden convenience food, and an increasingly sedentary lifestyle, there has been a sharp increase in the incidence of obesity and type 2 diabetes. Type 2 diabetes, accounts for around 90% of all diabetes sufferers and occurs when the body doesn't produce enough insulin, or when the cells of the body become insensitive to insulin, known as insulin resistance.

In recent years, what we know about diabetes has changed, with an improved understanding of the fundamental causes behind the condition. Although, there is a genetic link to diabetes, which predisposes individuals to type 2 diabetes. This risk is exacerbated by poor diet and lifestyle.  Genetic defects found so far only account for only a low percentage of all type 2 diabetes cases and really only increase the risk, rather than determining the development of the condition.

Type 2 diabetes is completely manageable and even reversible, but surprisingly there are many individuals that accept or ignore their condition, with a complete lack of interest in doing anything about it. To get type 2 diabetes under control and even eradicated, it simply takes a change in lifestyle – it seems like a small price to pay to add 10-20 years onto lifespan, as well as avoiding severe disability, limb amputation and blindness.

Reversing type 2 diabetes is not a new idea. Back during World War II,  Proffessor H. P. Himsworth noted that when food shortages removed the white flour, white sugar and excessive meat protein and fats from the typical British diet, the death rate from diabetes fell 50%. More recently a 5-year longitudinal Swedish study, consisting of 41 type 2 diabetes patients and 181 glucose intolerant individuals, used an initial 6 month pilot program constituting dietary changes and an increase in physical exercise. The results showed normalisation in glucose tolerance in more than 50% of individuals, 10-14% increase in glucose uptake directly contrasting to the control group which deteriorated a further 5-9 %. More than 50% of the diabetics were found to be in remission after 5 years. This demonstrates that long-term, diet and exercise intervention is successful in the treatment or prevention of type 2 diabetes and insulin resistance.

The clearest evidence that type 2 diabetes is reversible is following bariatric surgery. The normalisation of plasma glucose concentration follows within days of surgery, long before major weight loss has occurred. Additionally, improved control of blood glucose in type 2 diabetes, by moderate energy restriction, has been demonstrated. In a study of eleven people with type 2 diabetes, put on 8 weeks of a 600 kcal/day diet showed normalisation of both beta cell (the cells that store and release insulin release) function and hepatic insulin sensitivity. This was associated with decreased pancreatic and liver triacylglycerol stores. The abnormalities underlying type 2 diabetes are reversible by reducing dietary energy intake.

Wednesday
May062015

Causes and cures for diabetes

It is widely accepted that obesity is a major risk factor for the development of type 2 diabetes, which is generally associated with a reduction in insulin resistance. Around 70-80% of diabetic patients, are considered to be overweight or obese , with just a 5-8kg increase in weight doubling a persons risk for developing type 2 diabetes, whilst a weight gain of 20kg quadruples the risk. For women with a body mass index (BMI) of 35kg/m², their risk of diabetes increases 92-fold (as compared to those with an average healthy BMI of 23kg/m2), whilst for men with the same BMI, risk increases 42-fold. Further evidence exists that not only body weight is important, but also how the fat is distributed around the body. Visceral fat and a high waist to hip ratio, have been associated with higher incidence of type 2 diabetes. Interestingly, the reversal of the diabetic condition, occurs before any significant weight loss which suggests other underlying conditions.

Including more day-to-day exercise, is crucial for sufferers of type 2 diabetes. It improves the body's sensitivity to insulin, which is already in short supply, or difficult for the body to utilize. Not only does exercise help improve the diabetic condition, it can help reduce the risk of developing type 2 diabetes. A Harvard University study on the exercise habits of more than 70,000 women, showed that a 40 minute walk every day reduced type 2 diabetes risk, a notable 40%, and with a longer walk the risk could be decreased by an even larger percentage.

Chronic exercise also helps to increase blood flow which is important to help reduce the risk of neuropathy, a common neurological disorder associated with type 2 diabetes. In addition, studies have shown that a short-term reduction in daily physical activity, negatively affects insulin sensitivity.

Several in-depth studies have reported screen and/or television-viewing time to be detrimentally associated with weight gain, abnormal glucose metabolism, metabolic syndrome and type 2 diabetes. In a study of 2,761 women and 2,103 men, aged 30 years or older, sitting time was detrimentally associated with waist circumference, BMI, weight gain, two-hour post-load plasma glucose, and fasting insulin in both sexes. Television viewing time was detrimentally associated with all metabolic measures. In a cross-sectional study of 8,357 adults, aged 35 years or more and free from diabetes, time spent watching television was positively associated with increased 2 hour plasma glucose, fasting insulin, and insulin resistance and pancreas Beta cell function, in women. These findings highlights the negative relationship of sedentary behaviour of television viewing time and glycaemic measures, independent of physical activity time and adiposity status. This suggest an important role for reducing sedentary behaviour in the prevention of type 2 diabetes.

 

Toxins and diabetes

Research has also indicated a link between the development of type 2 diabetes and toxins, such as heavy metals, pesticides, plastic compounds including BPA, diesel exhaust, tobacco smoke, polycyclic aromatic hydrocarbons, hormones, radioactivity, viruses, bacteria and endocrine-disrupting chemicals. Organophosphate pesticides, including those used around the home, have been associated with weight gain and diabetes risk. In addition, studies have recently reported, that small increases in urban air pollution can decrease insulin sensitivity in healthy subjects, suggesting that air pollution contributes to the metabolic syndrome and a progression to type 2 diabetes. One suggested mechanism for this relationship, is through changes to the gut microbiome and ecology.

Oxidative stress by free radicals, has been shown to be a major factor in the complications that can arise with type 2 diabetes, such as the tissue damage often seen in diabetic patients. Those with type 2 diabetes, with higher blood glucose levels, will have a greater quantity of free radicals in their blood stream, when compared no non-diabetic individuals. Additionally, diabetes sufferers have significantly lower levels of antioxidants that eliminate free radicals, than normal. Many of the complications of diabetes come from advanced glycation endproducts (AGE), which occur when glucose cross-links with proteins in the body, a process closely associated with the formation of free radicals.

 

Supplements and diabetes

Research on the antioxidants, vitamins C and E, N-acetyl-Lcysteine (NAC), and alpha lipoic acid, have shown that they can improve diabetes by reducing the associated complications. When supplements of NAC, vitamins C and E, or both were given to type 2 diabetic mice, retained insulin secretions and decreased blood glucose levels were observed. Antioxidants may also be able to reduce the risk of birth defects in diabetic pregnancies by reducing oxidative stress. In a study of 21,831 men and women over 12 years, found increased blood levels of vitamin C may reduce the risk of developing diabetes by 62 per cent.

Additionally, numerous studies have demonstrated deficiencies of magnesium vitamin C the B complex, and other minerals and antioxidants in diabetes. The micronutrients have been shown to increase the number of Glut 4 transporters so that muscle cells are more sensitive to insulin and take in more sugar from the blood, even at rest. Even when insulin is not present by signalling the Glut 4 transporters the sugar is taken into the cell.

Lipoic acid has been used in Europe for more than twenty years in preventing and relieving complications of diabetes. German studies of diabetics with neuropathy, showed that following lipoic acid treatment, patients were sleeping better, feeling healthier and fitter, and some were able to reduce their doses of insulin. In another study lipoic acid was found to stimulate the regeneration of nerve fibres in diabetics, reducing the pain and numbness associated with neuropathy, as well as reducong AGE damage in diabetic patients.

Coenzyme Q10 (CoQ10) is not only a vital component in the process of energy formation, it is also superbly placed for its powerful anti-oxidant function. In tandem with the other members of this protective system, CoQ10 suffices to keep oxidative damage to a minimum and improve cellular metabolism in diabetics. Many other supplements have also been shown to benefit diabetics including Vitamin D and Resvaratrol.

Minerals shown to benefit diabetics include: chromium, vanadium and magnesium. Eating more magnesium-rich foods, like green leafy vegetables and nuts, may reduce the risk of type-2 diabetes, as suggested by a meta-analysis of observational studies. For every 100 milligram increase in magnesium intake, the risk of developing type-2 diabetes decreased by 15 per cent. The potential protective role of magnesium intake against type-2 diabetes may be due to improvement of insulin sensitivity, and on glucose control since magnesium can act as a co-factor for enzymes involved in the metabolism of glucose, and/or insulin secretion. Magnesium also has many anti-inflammatory and antioxidant properties.

Wednesday
May062015

Dietary Changes to Improve the Diabetic Condition  

It is important to cut out animal and cooked/professed fats (especially margarine), swapping them for mono-unsaturated fatty acids, like those found in fresh extra virgin olive oil, and omega-3 oils from both plants and fish. Increase your vegetable consumption, particularly raw vegetables and have vegetable smoothies. A healthy diet, containing a mix of vegetables, nuts and beans, has been shown to be particularly effective in regulating blood sugar and improving the diabetic condition. Similarly, fruits that improve the diabetic condition are pomegranates, blueberries, bitter melon and mulberry. Coffee, green and black tea, no sugar of course, have also been shown to be beneficial.

Herbs and spices are potent antioxidants, anti inflammatory and great sources of nutrients. The best evidence for efficacy is available for Coccinia indica and American ginseng. Other supplements with positive results include tumeric, Gymnema sylvestre, Aloe vera, Momordica charantia, nopal, parsley, holy basil, cloves, bay leaves and cinnamon. For example, 1, 3, or 6g of cinnamon per day reduces serum glucose, triglyceride, LDL-cholesterol, and total cholesterol decreases and glucose levels in type 2 diabetics.

Daily supplement (200mg, 3 times/day) of extracts from Milk Thistle (Silybum marianum) significantly lowered fasting glucose levels by 15% in type 2 diabetic patients. Milk Thistle was also found to have significant beneficial effects on glycosylated haemoglobin (AGE) levels, total cholesterol and LDL-cholesterol levels, and triglyceride levels in diabetics.

Additionally, supplementation with olive leaf polyphenols for 12 weeks significantly improved insulin sensitivity and pancreatic β-cell secretory capacity in overweight middle-aged men at risk of developing the metabolic syndrome. The leaves of the olive plant (Olea europaea L.) have been used for centuries in folk medicine to treat diabetes. According to animal and in vitro studies, olive leaf polyphenols, have antioxidant, hypoglycaemic, antihypertensive, antimicrobial, and anti-atherosclerotic properties.

Many studies have demonstrated that diabetes type 2 can be reversed through diet and lifestyle changes. To reverse decades of damage more emphasis needs to be put on a highly nutritious eating program, improved digestion, and physical activity - It takes a lot to reverse 20 or 30 years of damage. In most diabetes programs little emphasis has been placed on good digestion. Heal the digestive system to allow nutrients to be absorbed and transported around the body. The digestive system is also one of the major sources of inflammation and oxidation in the body. A few basic requirements to help with digestion is to eat more raw foods, supplement with digestive enzymes, prebiotics and probiotics. Probiotics have also been shown to reverse some of the conditions of diabetics. For example, one study demonstrated that, probiotic treatment reduced the fasted insulin levels, but improved the insulin secretion upon glucose challenge, indicating an improved metabolic flexibility and restoration of normal glucose metabolism, and a potential beneficial effect on metabolic syndrome.

With today's understanding of the condition, there really is no excuse to suffer with type 2 diabetes. With a common sense approach it is completely reversible. There are now more than 30 books and hundreds of websites written by medical professionals showing that diabetes can be reversed. In the Foreword to the book “There is a cure for diabetes” by Dr Gabriel Cousens, a leader in the field of reversing diabetes, Brian M Connolly writes “I was able to go from a dangerously high Type-2 diabetic condition, with a glucose reading of 292, down to a diabetes free reading of 113 in just 9 days”. Recently I met John from Townsville who went from 5 insulin injections a day to being a non-diabetic in a few weeks. What is your excuse?

Tuesday
Mar172015

Toxic load adds to your weight load

Although high-calorie fast foods and soft drinks are easily available, and people spend more time participating in sedentary activities such as watching television or using a computer, these factors are insufficient to explain the huge increase in obesity observed during the 20th century. The often overlooked obesogenic chemicals likely play an important role in the obesity and diabetes pandemic. Studies dating back to the 1970s have shown that low-dose chemical exposures were associated with weight gain in experimental animals 1. Since then, a growing number of studies show links between toxins and weight gain, obesity and diabetes. Known or suspected culprits behind negative epigenetic changes include toxins such as heavy metals, pesticides, plastic compounds including BPA, diesel exhaust, tobacco smoke, polycyclic aromatic hydrocarbons, hormones, radioactivity, viruses, bacteria and endocrine-disrupting chemicals.

The main role of fat cells is to store energy and release it when needed. Scientists now know that fat tissue acts as an endocrine organ, releasing hormones related to appetite and metabolism. Research to date suggests that different obesogenic compounds may have different mechanisms of action, some affecting the number of fat cells, others the size of fat cells, and still others the hormones that affect appetite, satiety, food preferences, and energy metabolism. Another mechanism through which these chemical obesogens can contribute to weight gain is through their impact on the gut microbiome, linking gut ecology and environmental chemicals to obesity and diabetes 2.

BPA, or bisphenol A, is a chemical found in everything from plastic bottles to metal food containers may be partly to blame for excess weight. BPA has been shown to alter the body’s metabolism, increasing weight gain and making it difficult to lose weight. A number of studies have reported elevated levels of BPA in obese and overweight individuals 3. BPA levels have been related to obesity in US studies 4,5 and in the Chinese population 6. In both American and Chinese schoolchildren, urinary BPA levels were associated with BMI 7-11. In a study of 1,326 children, girls between ages nine and 12 with high BPA levels had double the risk of being obese compared to girls with low BPA levels, validating previous animal and human studies. The chemical can alter the body’s metabolism and make it harder to lose weight. Girls with high levels of BPA—two micrograms per liter or more—were two times more likely to be obese than girls with lower levels of BPA in the same age group. Girls with very high levels of BPA, more than 10 micrograms per liter, were five times more likely to be obese, the study shows 12. Urinary BPA in pregnant women was related to BMI in their offspring at four years of age 13. Similar results were found in girls aged nine years 14. The oestrogenic properties of bisphenol A (BPA) have been known since 1936 15.

BPA has been shown to induce obesity in rodents in experimental settings 16,17. In animal experiments, mothers’ exposure to BPA is producing the same outcomes that we see in humans born light at birth: an increase in abdominal fat and glucose intolerance. BPA was seen to affect rodent fat cells at very low doses—1,000 times below the dose that regulatory agencies presume causes no effect in humans, whereas at higher doses researchers saw no effect. Hormone receptors typically respond to very low levels of hormone, so it makes sense that they may be activated by low levels of an endocrine mimic, whereas high levels of a chemical may actually cause receptors to shut down altogether, preventing any further response 18.

Children exposed to certain chemicals, POPs (Persistent Organic Pollutants), in the womb have a higher risk of being overweight. POPs include a wide variety of long-lasting chemicals that collect in fat and accumulate in wildlife and people. Some were made as pesticides, such as DDT, and others as electrical insulators including polychlorinated biphenyls (PCBs). POPs can also act as endocrine disruptors and disrupt hormone function. The developing foetus is exposed to POPs passed from the mother through the placenta.

Several longitudinal birth cohort studies have examined how prenatal exposure to DDT (now banned in most countries) and DDE affects child growth. Positive associations between prenatal DDT and DDE exposure and body mass index and overweight status have been reported in birth cohorts in Europe 19 and in the United States 20,21. In a study of 344 children, both PCB and DDE exposure led to an increased risk of weight gain in children. The link between being overweight and PCB and DDE levels in cord blood was stronger in girls than boys. DDT was associated with weight gain only in boys, especially in children with average or above average fat intakes. In some cases, children with higher POPs exposure were almost twice as likely to be overweight compared to children with lower exposure, depending on the pollutant and gender 20. In a study of 6,770 subjects aged six to 19 years, a dose-dependent increase in obesity was observed in the groups with highest urinary concentrations of 2,5-dichlorophenol (2,5-DCP) and reported a possible relationship between exposure to 2,5-DCP and obesity in children 22.

A growing body of evidence demonstrates that the use of certain organophosphate pesticides may also be associated with weight gain and diabetes risk 23.

Similar results of POPs have been found in animal experiments. Mice fed high-fat diets gained about 30% more weight and experienced raised blood sugar, compared to other mice eating the same high-fat diets, when they also ingested doses of a brominated flame retardant, hexabromocyclododecane (HBCD), which is used in building materials and insulation. It accumulates in the tissues of animals and humans, and previous animal studies have shown that it may disrupt hormones, metabolism and immune systems. Some evidence, mostly with lab animals, suggests that prenatal exposure to these obesogens can reprogram metabolism, leading to more fat cells and raising the risk of obesity later in life. The mice, which on average weighed 21 grams, were fed a high-fat diet with a high dose of flame retardant and gained an average of 21 grams. Mice fed the same diet without the chemical gained about 16 grams. That means that mice fed the extra flame retardant doubled their weight and put on around 25% more weight than the control group, and also had higher blood sugar and higher insulin levels than the unexposed mice. Their livers also weighed more and their adipose tissues were inflamed. Changes were also noted in the gene expression of their glucose transporters 24 HBCD is still used in large volumes.

Perfluorooctanoic acid (PFOA) is a ubiquitous chemical, used in nonstick cookware, Gore-Tex™ waterproof clothing, Scotchgard™ stain repellent on carpeting and mattresses; it is a potential endocrine disruptor. When pregnant mice were given PFOA during pregnancy, their offspring became obese in adulthood, reaching significantly higher weight levels than controls. Exposed offspring also had elevated levels of leptin, a hormone secreted by adipose tissue that affects appetite and metabolism.

Pre- and postnatal exposure to Firemaster®550 (FM550) has been associated with increased anxiety, obesity, and early-onset puberty in rats. Researchers reported further evidence that components of FM550 may act as environmental obesogens, stimulating adipogenesis (fat formation) at the expense of bone health. House dust in the US contains high levels of organophosphate flame-retardants, and their metabolites are ubiquitous in human urine. The authors estimated that young children could ingest 120 μg/day TPP from indoor exposure to dust alone.

Phthalates are plasticizers that also have been related to obesity in humans and occur in many PVC items, as well as in scented items such as air fresheners, laundry products, personal care products and many plastics. Studies suggest that phthalates have significant effects on obesity, especially after prenatal exposure at low doses (BMI) in children and adults 25.

In early studies, tributyltin (TBT), commonly found in home anti-mould and dust mite treatments, was given to pregnant mice and resulted in heavier offspring; even if the offspring eat normal food, they get slightly fatter. Tributyltin can exert toxicity through multiple mechanisms but most recently has been shown to bind, activate, and mediate gene regulation central to lipid metabolism and adipocyte biology. In support of this, long-term obesogenic effects on whole body adipose tissue are also reported 26. In another animal experiment, exposure to TBT for 45 days resulted in obesity and hepatic steatosis and induced the occurrence of insulin and leptin resistance 27.

Arsenic in drinking water has been found to promote a number of diseases that may stem from dysfunctional adipose lipid and glucose metabolism. Arsenic inhibits adipocyte differentiation and promotes insulin resistance; it also alters gene signaling for aberrant lipid storage and metabolism that may contribute to the pathogenesis of metabolic disease caused by environmental arsenic exposures 28. Similarly, a study of environmental contaminants in 114 seven- to nine-year-old Flemish children found a negative association between cadmium and abdominal and subcutaneous fat 29.

In a study of hypertensive rats, researchers found that short-term exposure to air pollution, over a 10-week period, elevates blood pressure in rats already predisposed to the condition 30. Another animal study from the same group found that early exposure to ultrafine particulates led to the accumulation of abdominal fat and insulin resistance in mice even if they ate a normal diet 30. The study compared mice fed a high-fat diet with those fed a normal, healthy diet, and exposed some members of both groups daily to ultrafine particulate matter, controlling for all other factors. In the end, all of the mice exposed to air pollution, including those fed a normal diet, had increased abdominal and subcutaneous fat. These findings suggest that fine particulate pollution exposure alone, in the presence of a normal diet, may lead to an increase in fat cell size and number, and also have a proinflammatory effect.

Experimental results also suggest a high-fat diet may exacerbate the health effects of inhaled PM2.5; this means obese people may be at increased risk. Mice breathing PM2.5 and eating a high-fat diet developed IR, systemic inflammation, and increased abdominal fat, compared with mice eating the same diet but breathing filtered air 31. This mechanism directly ties a known inflammatory mechanism in the pathogenesis of type 2 diabetes to exposure to environmental air pollution; the inflammatory damage likely creates a vicious cycle that can also contribute to cardiovascular disease and obesity. In addition, studies have recently reported that small increases in urban ambient PM2.5 can decrease insulin sensitivity in healthy subjects 32, suggesting that PM2.5 may contribute to metabolic syndrome and to the progression from metabolic syndrome to diabetes.

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